Man-made environmental electromagnetic energy (EEE) from the power and communications systems is pervasively present. Despite this, until recently there has been no serious consideration of the public-health consequences of chronic exposure to EEE. Now interest in all aspects of bioelectricity has been kindled by discovery of the importance of solid-state properties of biological tissue, and by recognition that biological growth-control systems function by means of voltages and currents comparable to those induced by EEE. In the US the emphasis has been on therapeutic application of very low levels of electromagnetic energy, and widespread clinical testing of various techniques is in progress. In a few cases proposed construction projects—a 765,000-volt transmission line in New York and a military radar in Massachusetts, for example—have involved some consideration of adverse side-effects of EEE. This evidence—and that from the USSR where the public-health consequences of EEE are under intensive study—have established that EEE is capable of causing biological changes in exposed subjects. A thorough independent review of public exposure patterns and a risk/benefit analysis are therefore required so that the true cost of specific technologies can be determined.